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a. ´´½¨xs±íÖмÆËã»úרҵѧÉúµÄ±¸·Ý
Create table xs_jsj as select * from xs where zym=’¼ÆËã»ú’;
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¡¡¡¡¡¡¡¡¡¡ Create table test (xm char(20) not null,zy varchar(30) default (‘¼ÆËã»ú’));
-- Create table
create table DEPT
(
DEPTNO NUMBER(2) not null,
DNAME VARCHAR2(14),
LOC VARCHAR2(13)
)
tablespace USERS
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SQL> desc test;
Name Type Nullable Default Comments
------- ------------ -------- ------- --------
COUNTRY VARCHAR2(20) Y &nb ......
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Ö´ÐÐÒÔÏÂsqlÓï¾ä´´½¨database link
create database link test_link --Á´½ÓÃû
connect to Óû§Ãû identified by ÃÜÂë
using '(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = Êý¾Ý¿â·þÎ ......
MS SQL ÖеÄIsNull()º¯Êý£º
IsNull ( check_expression , replacement_expression )
check_expression: ¿ÉÒÔÊÇÈκÎÀàÐÍ,½«Òª¼ì²éµÄ±í´ïʽ ²»Îª¿Õ£¬·µ»ØËü
replacement_expression: ÀàÐͱØÐëºÍcheck_expressionÏàͬ£¬check_expressionΪnull£¬·µ»ØËü
Õâ¸öº¯ÊýµÄ×÷ÓþÍÊÇ£ºÅжÏcheck_expressionÊÇ·ñΪ¿Õ£¬Îª¿Õ¾Í·µ» ......
Exam Number/Code : 1z0-047
Exam Name : Oracle Database SQL Expert
Questions and Answers : 278 Q&As
Update Time: 2010-04-15
1. Which two statements are true regarding the execution of the correlated subqueries? (Choose two.)
A. The nested query executes after the outer query returns th ......